Solutions of the Hodgkin-Huxley equations modified for potassium accumulation in a periaxonal space.
Solutions of the Hodgkin-Huxley equations modified for potassium accumulation in a periaxonal space.
复制标题
针对轴周空间钾积累而修改的霍奇金-赫胥黎方程的解。
DOI：
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发表时间：
1975
期刊：
影响因子：
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通讯作者：
R. FitzHugh
中科院分区：
文献类型：
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作者：
W. J. Adelman;R. FitzHugh
Hodgkin和Huxley方程进行了修改，以包括外部扩散屏障的特性，该屏障通过薄的轴突周空间与轴膜分离，其中钾离子积累为膜活性的函数。方程中的进一步修改考虑了新的gK值和新的函数，从Loligo pealei巨轴突的电压钳实验中获得的β-葡聚糖、β-葡聚糖、α-葡聚糖和β-葡聚糖。方程在PDP-11计算机上用Gear预估-校正数值方法求解。与原始的Hodgkin和Huxley方程相比，修改后的膜电位方程给出：1）更准确地表示膜动作电位的下降和下冲阶段，2）更准确地表示阈值和潜伏期，3）轴突周围空间钾离子浓度Ks增加约1 mM/脉冲，4）正确预测短时间重复刺激诱发的膜动作电位序列中下冲下降或轴周钾离子蓄积的时间过程和幅度;以及5）在长持续时间恒定电流刺激期间适应的稍微更准确的表示（有限训练和非重复响应）。
Hodgkin and Huxley equations were modified to include the properties of an external diffusion barrier separated from the axolemma by a thin periaxonal space in which potassium ions accumulate as a function of membrane activity. Further modifications in the equations took into account new values for gK and new functions for alphan, betan, alphah, and betah derived from voltage clamp experiments on Loligo pealei giant axons. Equations were solved on a PDP-11 computer using the Gear predictor-corrector numerical method. In comparison with the original Hodgkin and Huxley equations, the modified equations for membrane potentials gave: 1) more accurate representations of the falling and undershoot phases of the membrane action potential, 2) more accurate representation of thresholds and latencies, 3) increases in the periaxonal space potassium ion concentration, Ks, of about 1 mM/impulse, 4) proper predictions of the time course and magnitude of either undershoot decline or periaxonal potassium ion accumulation during trains of membrane action potentials elicited by repetitivie short duration stimuli, and5) a somewhat more accurate representation of adaptation (finite train and nonrepetitive responses) during long duration constant current stimulation.